1. Field of the Invention
This is invention relates to a solid material flow-separating method, particularly to a solid material flow-separating method for conducting a separation treatment on fine solid material in fluid such as liquid, and more particularly to a solid material flow-separating method for separating fine solid pollutant floating in polluted water
2. Description of Related Art
Various kinds or methods have been conventionally proposed and used to purify polluted water such as various kinds of waste water, river water polluted by the waste water, etc. The conventional purifying methods for the polluted water are mainly classified into the following two methods. One method is (1) a chemical treatment method in which pollutant in polluted water is subjected to a chemical treatment to make the pollutant harmless, and the pollutant is agglomerated and precipitated to separate the pollutant From the water, and the other method is (2) a biological treatment method in which the pollutant is biologically made harmless, for example, by a biomembrane or active sludge, and then the pollutant is flocculated to separate the pollutant from the water.
In most of recent biological treatments, microorganism is fixed to a prescribed carrier to form a biomembrane. In order to from the biomembrane there have been proposed a method of alternately disposing aerobic state and anaerobic state on the carrier, and a method of simultaneously disposing aerobic state and anaerobic, state on a carrier to form a hollow carrier as disclosed Japanese Laid-open Patent Application No. 63-310696.
Further, for the purpose of purification of polluted river water, an inter-conglomerate contact oxidation method of purifying river water using river beds has been recently proposed and already practically used as a biological treatment method. In the inter-conglomerate contact oxidation method, a conglomerate layer is formed by effectively using conglomerate such as gravel in river or the like, and river water is made to flow through the conglomerate layer for a biological treatment. By this method, BOD (Biochemical Oxygen Demand) and SS (Suspended Solid) can be greatly reduced, and thus spotlight of attention is focused on this method as a purification method for polluted water such as polluted river water.
Any one of the conventional polluted water purifying methods as described above requires two steps of treatments of a reaction treatment system and a precipitation/separation treatment system in both of the chemical treatment and the biological treatment.
The inventor has made various studies on purification for polluted water in a water system such as river. Particularly for the purpose of improvement in practicability by effectively using the inter-conglomerate contact oxidation method, the applicant has considered an improved technique to the inter-conglomerate contact oxidation method and developed a separation material constituting a purifying treatment system which is completely different from the conventional treatment for polluted water. This separation material and a polluted-water treatment using the separation material are proposed in Japanese Laid-open Patent Application No. Hei-3(1991)-221110.